I took a pretty decent spill last week trying to grind a rail, ended up bailing and fell directly on my left shoulder (it was icy as hell too, midwest FTL). Anyway, the first 2 days I couldn't even lift my arm over my head. It has gotten better but i still feel the pain when I try and move my left arm from the left to the right while holding on to something/putting pressure on it (like making a one handed turn in a car or something, if i steer to the right with the left arm tightly gripping the wheel it hurts).

Wondering if anyone has had something similar. Does this sound like a rotator cuff issue? I know we're not Doctors here but just trying to get some input. I'm going boarding again on Friday and my left arm is the arm I use to push myself up off the ground when I'm getting up, etc.

I partially tore mine landing a jump in a mogul field (dumb). It sounds similar to your problem: I couldn't lift my arm for days and had to do these exercises where you walk your fingers up the wall with your arm straight. I can't remember how long it took to get better. Maybe a week to move decent again. Throwing a ball may be an issue for a while though if you do any of that.

You can tell it's your rotator by if it feels like the pain is inside your shoulder. Usually I can push on my arm just below my shoulder blade and feel it.

I done mine before from Mma but what my physio made me do was lay back on a medicine ball and roll it about on the sore area and then while leaning on it VERY SLOWLY move my arm up and down and out to the side to work the muscle from different angles.

I done that for about 3 days 2 times a day and it felt great after. Obviously without actually being able to see what's happening with you I can't say it is the same thing but if you can find a hard ball to roll on I would def give it a try